Revert "test(repository-plugin): drop the skill contribution from the preset-composed e2e"

This reverts commit f12c131ee9fdbc01b9294c8dc2c73cd36ab717cf.

The layered host skill registry closes the gap the bypass recorded: a
repository plugin's skill root registers into the global layer and reaches
every preset-composed session's catalog, so the fixture declares its skill
root again and the e2e proves the full skill, MCP, and TypeScript
contribution set. The accidental .claude/launch.json from that commit goes
with it.

apps/cli/tests/fixtures/github-repository-plugin/.dsh-plugin/package.json

@@ -12,6 +12,9 @@
     "prepack": "tsc --noEmit && tsdown src/plugin.ts src/mcp-server.ts --no-config --tsconfig tsconfig.json --out-dir lib --platform node --target es2024 --clean && dsh-plugin-prepare"
   },
   "dsh": {
+    "skills": [
+      "../skills"
+    ],
     "mcpServers": "./.mcp.json",
     "entry": "./lib/plugin.mjs"
   },